Simulation Analysis of an Impeller Percussive Drilling Tool Based on Rotation Law

Percussion drilling tool is considered to be an efficient method to promote the rate of penetration (ROP) among the numerous drilling tools, therefore, an novel impeller percussion drilling tool is proposed in this paper, and the basic principle of impact drilling tool is: when the fluid flows through the impeller, the flowing fluid push the impeller rotating, lead to the fluid pressure periodical fluctuation as a result of fluid channel cross-section area variation, and eventually convert the hydraulic energy to impact load through the rotating impeller. In order to predict the output load type generated and the fluid pressure changes of the tool, four rotary machinery interaction models are established, and the influence of flow rate, frequency and displacement on the output load variation is analyzed. Results indicates that load generated of model 3 is sine-shaped, and model 3 presents the best performance, and it is demonstrated that the amplitude of the load is dependent on the flow rate, number of impeller, vane thickness, distance between the impeller and the wall, the rotary frequency. Thereafter, optimal working parameters are recommended for the percussion tool in the practical design and application, which will provide a guidance for the design of down-hole percussion drilling tools.